Cornelius Tacitus (56-120 AD) was one of the greatest of the Latin historians. In his book Germania, Tacitus wrote (chap 34) that ‘Pillars of Hercules’ were located in the land of the Frisians near the Rhine. This is just one classical reference that highlights the fact that Gibraltar was not the only possible site of these landmarks. It would appear that the ‘Pillars’ may have existed at the same time at a number of locations or changed their position over time.